#include <stdio.h>
#include <unistd.h>

int main()
{
    printf("printf");
    fwrite("fwrite", 1, 6, stdout);
    fprintf(stdout, "%s%s", "fprintf", "1");
    write(1, "write", 5);
    sleep(3);
    fflush(stdout);
    sleep(1);
    write(1, "无流缓存", 12);
    sleep(1);
    printf("\n");
    return 0;
}
